Tools

# How does a potentiometer work?

potentiometer is an electricians and measurement component . As its name indicates, it is used to measure and control power through voltages.

## What is a potentiometer?

potentiometer  is an instrument generally used in a technical field in order to determine the difference in electrical potential   between two electrical terminals . The potential difference is what is commonly known as voltage.

## How does a potentiometer work?

A potentiometer has a simple operation, it has a variable resistance at each end and a third connection to a slider, which will allow us to increase or decrease the resistance itself . The purpose of this is to get a variable value between the connections, which we can control ourselves.

To know in depth how a potentiometer works , it is important to know its components and what function each of them fulfills. It basically consists of a variable resistor , which changes value as the current increases.

This resistor has three terminals to which the voltage to be measured is connected. By varying the resistance, the potential difference between the terminals varies. Therefore the value of the voltage is determined by the variation of the resistance.

## Types of potentiometer

There are different types of potentiometers, and these classifications depend on the variation of their resistance , on the type of control and (in modernity) on its technology .

### Potentiometer according to  variations in resistance

• Linear potentiometer: Where the resistance varies linearly to the variation of the angle that the resistance was made to vary.
• Logarithmic potentiometer : The resistance varies depending on the angle but this time in an inverse exponential way.
• Sinusoidal potentiometer : Varies depending on the sine of the angle.
• Antilogarithmic potentiometer: varies exponentially to the angle of rotation.

### Potentiometer according to  type of control

• Rotary potentiometer : They are controlled by turning a shaft. They are long lasting and take up little space.
• Sliding Potentiometer : It is controlled by running a cursor in a straight way. Widely used in graphic equalizers.
• Multiple Potentiometer : They have coaxial axes. This way they take up much less space.

### digital potentiometer

They are those whose operation simulates that of an analog potentiometer through an integrated circuit, it is characterized by greater precision.

## Applications of a potentiometer

Potentiometers are used for many electrical and electronic devices. They can be applied both to carry out a control action, that is to say, to modify some condition, or as an adjustment function, that is to say, to detect some irregularity and correct it. Here some examples:

• Audio control : The volume of a stereo is controlled through a potentiometer.
• Fan : The speed at which it rotates (0 ; 1 ; 2 ; 3 ; 4 ; 5) is determined with the potentiometer; when it is at zero it means that there is no contact, therefore it is off.
• Lighting: When regulating the intensity of light.
• Control systems : It is very common to find it in control systems in order to act as meters of some particular variable.